1. Field of the Invention
The present invention relates generally to devices for blowing air across the surface of vehicles to dry moisture from such vehicles, and more particularly, to devices which provide an oscillating air flow pattern to cover the entire surface of the vehicle.
2. Description of the Relevant Art
Automated vehicle washing systems have been available for many years to automatically wash and dry vehicles. Large volume vehicle washing systems typically include a conveyor system for moving a vehicle through a series of washing and rinsing stations, and finally, through a drying station which serves to remove moisture from the surface of the vehicle.
A variety of drying stations are known for removing moisture from the vehicle. In one such known drying station, an air duct is pivotally secured to an overhead frame member. The air duct is coupled by flexible hosing to an air blowing device. As the vehicle passes through the drying station, rollers or followers secured to the air duct contacted the upper surfaces of the vehicle and lift the overhead air duct about its pivotal supports to follow the contour of the vehicle. While such drying stations perform the function of drying the vehicle, rather large blower devices must be used to overcome the pressure losses which occur within the flexible hosing. The need for using such large blower devices increases electrical usage and the noise levels associated with such drying stations. Moreover, such drying stations present the disadvantage that the rollers or followers contact the vehicle surface and may potentially scratch the finish or break accessories protruding from the surface of the vehicle. In addition, the flexible hosing that couples the vent to the blower often dries out and cracks open.
So-called touch-free drying stations are also known wherein one or more blower fans are coupled to fixed vents positioned along the sides and above the station. While the fixed vents avoid any contact with the surface of the vehicle, the fixed position vents also have disadvantages. For example, to ensure adequate coverage of the entire vehicle surface, the vent openings of the air blowing fans are often formed with elongated openings measuring two to three feet in length to discharge a wide swath of air. However, because the vent openings are so large, air pressure drops along the ducting between the fans and the vents are so large that either output air flow speed is reduced, or to compensate, larger, more powerful, and noisier fans are required to maintain adequate output air flow.
A third type of drying station is known wherein a single large blower forces air into a distribution manifold to which several oscillating pivoting-cone nozzles are secured. The movable nozzles are engaged by flexible seals to permit movement of the nozzles while preventing air from escaping around the sides of each nozzle. A drive mechanism causes the nozzles to oscillate for emitting a number of oscillating air streams from the distribution manifold. The oscillating streams of air emitted by such nozzles ensure adequate coverage for vehicles having a wide variety of contours. However, due to pressure losses within the distribution manifold, a relatively large blower fan and motor must be used to create a high pressure in the manifold, resulting in significant consumption of electrical power, large power surges when the blower motor turns on and off, and increased noise due to the size of the blower motor required and the drop in pressure through the manifold. Also, the flexible seals used to seal the nozzles to the distribution manifold dry out and crack, resulting in air leaks, lower pressure and extensive maintenance.
Accordingly, it is an object of the present invention to provide a blowing device that provides an oscillating stream of air for drying vehicles and the like while avoiding significant drops in air pressure due to extensive air ducting.
It is another object of the present invention to provide such a blowing device adapted to dry the entire surface of the vehicle without any physical contact between the blowing device and the surface of the vehicle.
It is still another object of the present invention to provide such a blowing device which can operate at reduced air pressures, and hence, lower noise levels, and still provide an oscillating air stream of sufficient pressure to adequately dry the surface of washed vehicles and the like.
A further object of the present invention is to provide such a blowing device that provides an oscillating stream of air and which provides a relatively higher volume of air for a given sized blower fan and operating pressure.
A yet further object of the present invention is to provide such a blowing device which provides oscillating air streams while using a series of smaller horsepower blower motors, as compared with a single larger horsepower blower motor, in order to lessen power surges on the electrical supply lines from which such blower motors are powered.
Still another object of the present invention is to provide such a blowing device which is inexpensive to construct and maintain.
Yet another object of the present invention is to provide such a blowing device which requires relatively little floorspace.
These and other objects of the present invention will become more apparent to those skilled in the art as the description of the present invention proceeds.